1. Field of the Invention
A method of electroconductive fastening of substrates, current collectors and terminals of similar and dissimilar materials, especially carbon fibers and metal foils used in the construction of alkali metal and alkaline earth metal batteries, and other electrochemical devices, which method uses the application of pressure, and tape having an adhesive layer thereon to secure the substrates, current collectors, and terminals together.
2. Description of the Prior Art
In constructing alkaline metal and alkaline earth metal batteries and other electrochemical devices, it is often necessary to electroconductively connect various carbon fiber current collectors, or substrates to metal terminals. The prior art methods of connection used various electroconductive glues or soldering. There are many disadvantages in using electroconductive glues, since their electroconductivity when assembled may be poor, or the resistance to chemicals used in the batteries may be low. As a result, the materials may separate and/or suffer from diminished electrical conductivity.
The use of hot soldering is limited as it can only be done between similar metals, and not between metals and other materials such as carbon fibers, nor can it be used to join two pieces of carbon fiber material.
The use of cold soldering with a soft metal as the conductive glue is possible, but any cold soldering metal except gold will eventually suffer from galvanic corrosion caused by the presence of carbon fibers, will disintegrate and lose its conductivity, especially at higher voltage and current levels. Gold as a cold soldering material is too expensive to be practical for use in large quantities in batteries and other electrochemical devices.
The method of fastening of the invention provides a superior product that does not suffer from prior art problems and provides many advantages over the prior art.